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<div class="titlepage"><div><div><h6 class="title">
<a name="beast.ref.boost__beast__websocket__stream.read_some.overload1"></a><a class="link" href="overload1.html" title="websocket::stream::read_some (1 of 4 overloads)">websocket::stream::read_some
          (1 of 4 overloads)</a>
</h6></div></div></div>
<p>
            Read some message data.
          </p>
<h7><a name="beast.ref.boost__beast__websocket__stream.read_some.overload1.h0"></a>
            <span class="phrase"><a name="beast.ref.boost__beast__websocket__stream.read_some.overload1.synopsis"></a></span><a class="link" href="overload1.html#beast.ref.boost__beast__websocket__stream.read_some.overload1.synopsis">Synopsis</a>
          </h7><pre class="programlisting"><span class="keyword">template</span><span class="special">&lt;</span>
    <span class="keyword">class</span> <a class="link" href="../../../concepts/DynamicBuffer.html" title="DynamicBuffer"><span class="emphasis"><em>DynamicBuffer</em></span></a><span class="special">&gt;</span>
<span class="identifier">std</span><span class="special">::</span><span class="identifier">size_t</span>
<span class="identifier">read_some</span><span class="special">(</span>
    <span class="identifier">DynamicBuffer</span><span class="special">&amp;</span> <span class="identifier">buffer</span><span class="special">,</span>
    <span class="identifier">std</span><span class="special">::</span><span class="identifier">size_t</span> <span class="identifier">limit</span><span class="special">);</span>
</pre>
<h7><a name="beast.ref.boost__beast__websocket__stream.read_some.overload1.h1"></a>
            <span class="phrase"><a name="beast.ref.boost__beast__websocket__stream.read_some.overload1.description"></a></span><a class="link" href="overload1.html#beast.ref.boost__beast__websocket__stream.read_some.overload1.description">Description</a>
          </h7><p>
            This function is used to read some message data. The call blocks until
            one of the following is true:
          </p>
<div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; ">
<li class="listitem">
                Some message data is received.
              </li>
<li class="listitem">
                A close frame is received. In this case the error indicated by the
                function will be <a class="link" href="../../boost__beast__websocket__error.html" title="websocket::error"><code class="computeroutput"><span class="identifier">error</span><span class="special">::</span><span class="identifier">closed</span></code></a>.
              </li>
<li class="listitem">
                An error occurs.
              </li>
</ul></div>
<p>
            The algorithm, known as a <span class="emphasis"><em>composed operation</em></span>, is
            implemented in terms of calls to the next layer's <code class="computeroutput"><span class="identifier">read_some</span></code>
            and <code class="computeroutput"><span class="identifier">write_some</span></code> functions.
            Received message data is appended to the buffer. The functions <a class="link" href="../got_binary.html" title="websocket::stream::got_binary"><code class="computeroutput"><span class="identifier">got_binary</span></code></a> and <a class="link" href="../got_text.html" title="websocket::stream::got_text"><code class="computeroutput"><span class="identifier">got_text</span></code></a> may be used to query
            the stream and determine the type of the last received message. The function
            <a class="link" href="../is_message_done.html" title="websocket::stream::is_message_done"><code class="computeroutput"><span class="identifier">is_message_done</span></code></a> may be called
            to determine if the message received by the last read operation is complete.
            Until the call returns, the implementation will read incoming control
            frames and handle them automatically as follows:
          </p>
<div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; ">
<li class="listitem">
                The <a class="link" href="../control_callback.html" title="websocket::stream::control_callback"><code class="computeroutput"><span class="identifier">control_callback</span></code></a> will be
                invoked for each control frame.
              </li>
<li class="listitem">
                For each received ping frame, a pong frame will be automatically
                sent.
              </li>
<li class="listitem">
                If a close frame is received, the WebSocket closing handshake is
                performed. In this case, when the function returns, the error <a class="link" href="../../boost__beast__websocket__error.html" title="websocket::error"><code class="computeroutput"><span class="identifier">error</span><span class="special">::</span><span class="identifier">closed</span></code></a> will be indicated.
              </li>
</ul></div>
<h7><a name="beast.ref.boost__beast__websocket__stream.read_some.overload1.h2"></a>
            <span class="phrase"><a name="beast.ref.boost__beast__websocket__stream.read_some.overload1.return_value"></a></span><a class="link" href="overload1.html#beast.ref.boost__beast__websocket__stream.read_some.overload1.return_value">Return
            Value</a>
          </h7><p>
            The number of message payload bytes appended to the buffer.
          </p>
<h7><a name="beast.ref.boost__beast__websocket__stream.read_some.overload1.h3"></a>
            <span class="phrase"><a name="beast.ref.boost__beast__websocket__stream.read_some.overload1.parameters"></a></span><a class="link" href="overload1.html#beast.ref.boost__beast__websocket__stream.read_some.overload1.parameters">Parameters</a>
          </h7><div class="informaltable"><table class="table">
<colgroup>
<col>
<col>
</colgroup>
<thead><tr>
<th>
                    <p>
                      Name
                    </p>
                  </th>
<th>
                    <p>
                      Description
                    </p>
                  </th>
</tr></thead>
<tbody>
<tr>
<td>
                    <p>
                      <code class="computeroutput"><span class="identifier">buffer</span></code>
                    </p>
                  </td>
<td>
                    <p>
                      A dynamic buffer to append message data to.
                    </p>
                  </td>
</tr>
<tr>
<td>
                    <p>
                      <code class="computeroutput"><span class="identifier">limit</span></code>
                    </p>
                  </td>
<td>
                    <p>
                      An upper limit on the number of bytes this function will append
                      into the buffer. If this value is zero, then a reasonable size
                      will be chosen automatically.
                    </p>
                  </td>
</tr>
</tbody>
</table></div>
<h7><a name="beast.ref.boost__beast__websocket__stream.read_some.overload1.h4"></a>
            <span class="phrase"><a name="beast.ref.boost__beast__websocket__stream.read_some.overload1.exceptions"></a></span><a class="link" href="overload1.html#beast.ref.boost__beast__websocket__stream.read_some.overload1.exceptions">Exceptions</a>
          </h7><div class="informaltable"><table class="table">
<colgroup>
<col>
<col>
</colgroup>
<thead><tr>
<th>
                    <p>
                      Type
                    </p>
                  </th>
<th>
                    <p>
                      Thrown On
                    </p>
                  </th>
</tr></thead>
<tbody><tr>
<td>
                    <p>
                      <code class="computeroutput"><span class="identifier">system_error</span></code>
                    </p>
                  </td>
<td>
                    <p>
                      Thrown on failure.
                    </p>
                  </td>
</tr></tbody>
</table></div>
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      Falco<p>
        Distributed under the Boost Software License, Version 1.0. (See accompanying
        file LICENSE_1_0.txt or copy at <a href="http://www.boost.org/LICENSE_1_0.txt" target="_top">http://www.boost.org/LICENSE_1_0.txt</a>)
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